<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>选择器优先级</title>
</head>
<style>
    #p1{
        color: crimson;
    }
    .classname{
        color: blue;
    }
    p{
        color: cyan;
    }
    /*id大于类大于标签*/
</style>
<body>
<p id="p1" class="classname">低头思故乡</p>
</body>
</html>